Low density ethylene-based compositions with improved melt strength, output, and mechanical properties

ABSTRACT

The invention provides a composition comprising the following:
     A) a first ethylene-based polymer, formed by a high pressure, free-radical polymerization process, and comprising the following properties:
       a) a Mw(abs)/Mw(GPC)&lt;2.2; and   b) a MS versus I2 relationship: MS≥C×[(I2) D ], where C=13.5 cN/(dg/min) D , and D=−0.55,   c) a melt index (I2) from 0.1 to 0.9 g/10 min; and   
       B) a second ethylene-based polymer; and
       wherein the second ethylene-based polymer has a melt index (I2) from 0.1 to 4.0 g/10 min.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application61/826,271, filed on May 22, 2013.

BACKGROUND

Blown film production lines are typically limited in output by bubblestability. Blending Linear Low Density Polyethylene (LLDPE) with LowDensity Polyethylene (LDPE) increases bubble stability, in part due tothe higher melt strength of the LDPE. The increase in melt strength inpart provides for an increase in film output. However, too high a meltstrength, especially as with broad molecular weight distribution (MWD),autoclave LDPEs with fractional melt indexes, can cause gels, limitingdrawdown capabilities, which can result in poor quality films. Also,high melt strength LDPE resins typically have reduced optics. Thus,there is a need for new compositions containing ethylene-based polymers,such as tubular LDPEs, that have an optimized balance of melt strength,optics and mechanical properties, for blown film applications.

Linear Low Density Polyethylene (LLDPE) is typically more difficult toprocess on a blown film line with generally poorer bubble stability, orlower maximum output (mass/time such as pounds per hour) than LowDensity Polyethylene (LDPE). Films made with Linear Low DensityPolyethylene (LLDPE), however, generally have better film mechanicalproperties than those made with Low Density Polyethylene (LDPE). Filmprocessing and film properties are to a large extent optimized for blownfilms by blending Linear Low Density Polyethylene (LLDPE) with LowDensity Polyethylene (LDPE). Blending in lower amounts of LDPE intoLLDPE typically leads to improved processing compared to pure LLDPE,improved optical properties, and acceptable mechanical properties.Blending in high amounts of LDPE into LLDPE improves processing furtherand allows thick film of a very large bubble diameter to be produced,while the mechanical and optical film properties are maintained orimproved over film made from pure LDPE. LDPE-rich films are alsoespecially suited to shrink films, such as collation shrink films, wherethe LDPE imparts good shrinkage behavior which cannot be achieved by theuse of a LLDPE alone. In summary, the LDPE blend component contributestypically to the processability, optical properties, and shrinkperformance, while the LLDPE blend component contributes to themechanical properties.

There is a need for new compositions that can increase the melt strengthand the processing performance over conventional LDPE/LLDPE blends, andwhich can be made at low conversion costs in a tubular process.Furthermore, there is need for LDPE/LLDPE compositions with improvedperformance in processing (maximum line speed and or large bubbleoperation) and/or film properties (mechanical and shrink performanceand/or optical appearance).

Low density polyethylenes and blends are disclosed in the following:U.S. Publication 2014/0094583; U.S. Pat. No. 5,741,861; U.S. Pat. No.7,741,415; U.S. Pat. No. 4,511,609; U.S. Pat. No. 4,705,829; U.S.Publication No. 2008/0038533; JP61-241339 (Abstract); JP2005-232227(Abstract); and International Publication Nos. WO2010/144784,WO2011/019563, WO 2010/042390, WO 2010/144784, WO 2011/019563, WO2012/082393, WO 2006/049783, WO 2009/114661, US 2008/0125553,EP0792318A1 and EP 2239283B1. However, such polymers do not provide anoptimized balance of high melt strength and improved film mechanicalproperties, for blown film applications. Thus, as discussed above, thereremains a need for new ethylene-based polymer compositions that have anoptimized balance of melt strength, optics, processability and output,and good shrinkage. These needs and others have been met by thefollowing invention.

SUMMARY OF INVENTION

The invention provides a composition comprising the following:

-   A) a first ethylene-based polymer, formed by a high pressure,    free-radical polymerization process, and comprising the following    properties:    -   a) a Mw(abs)/Mw(GPC)<2.2; and    -   b) a MS versus I2 relationship: MS≥C×[(I2)^(D)], where C=13.5        cN/(dg/min)^(D), and D=−0.55,    -   c) a melt index (I2) from 0.1 to 0.9 g/10 min; and-   B) a second ethylene-based polymer; and    -   wherein the second ethylene-based polymer has a melt index (I2)        from 0.1 to 4.0 g/10 min.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are schematics of a polymerization flow schemes. FIG. 1Arepresents a general flow scheme. FIG. 1B provides more detail of thedischarge of the primary compressor system.

FIG. 2 depicts the maximum output on the blown film line describedherein versus the % LDPE in LLDPE1 used in the film.

FIG. 3 depicts the MD shrink tension measured on a film made at standardrate versus the % LDPE in LLDPE1 used in the film.

FIG. 4 depicts the melt strength measured on blends versus the % LDPE inLLDPE1.

DETAILED DESCRIPTION

As discussed above, the invention provides a composition comprising thefollowing:

-   A) a first ethylene-based polymer, formed by a high pressure,    free-radical polymerization process, and comprising the following    properties:    -   a) a Mw(abs)/Mw(GPC)<2.2; and    -   b) a MS versus I2 relationship: MS≤C×[(I2)^(D)], where C=13.5        cN/(dg/min)^(D), and D=−0.55,    -   c) a melt index (I2) from 0.1 to 0.9 g/10 min; and-   B) a second ethylene-based polymer; and    -   wherein the second ethylene-based polymer has a melt index (I2)        from 0.1 to 4.0 g/10 min.

The composition may comprise a combination of two or more embodimentsdescribed herein.

In feature a) above, the Mw(abs) and Mw(GPC) are each determined by GPCMethod A as described herein.

In feature b) above, the Melt Strength (MS) is determined at 190° C.;see test method described herein.

In one embodiment, the composition has a density from 0.910 to 0.925g/cc, further from 0.915 to 0.922 g/cc.

In one embodiment, the composition has a melt index (I2) from 0.1 to 1.5g/10 min, further from 0.2 to 1.0 g/10 min, and further from 0.3 to 0.9g/10 min.

In one embodiment, the composition has a Melt Strength (190° C.) from 5to 40 cN, further from 10 to 40 cN, further from 20 to 40 cN, furtherfrom 15 to 40 cN.

In one embodiment, when an inventive composition is formed into a film,via a blown film process, the maximum output rate is at least 15 percentgreater than the maximum output rate of a similar film formed from asimilar composition, except the composition contains 100 weight percentof the second ethylene-based polymer, based on the sum weight of thefirst ethylene-based polymer and the second ethylene-based polymer.

In one embodiment, the second ethylene-based polymer has a melt index(I2) from 0.2 to 3.5 g/10 min, further from 0.3 to 3.0 g/10 min, furtherfrom 0.4 to 2.5 g/10 min.

In one embodiment, the second ethylene-based has a density from 0.870 to0.969 g/cc, further from 0.890 to 0.950 g/cc, further from 0.910 to0.940 g/cc, further from 0.915 to 0.930 g/cc.

In one embodiment, the second ethylene-based polymer is present in anamount from 5 to 95 weight percent, further from 10 to 95 weightpercent, further from 20 to 95 weight percent, further from 30 to 95weight percent, based on weight of the composition.

In one embodiment, the second ethylene-based polymer is present in anamount from 40 to 95 weight percent, further from 50 to 95 weightpercent, further from 60 to 95 weight percent, further from 70 to 95weight percent, based on weight of the composition.

In one embodiment, the second ethylene-based polymer is anethylene/α-olefin interpolymer, and further a copolymer. In a furtherembodiment, the ethylene/α-olefin interpolymer is a heterogeneouslybranched ethylene/α-olefin interpolymer, and further a copolymer.Suitable alpha-olefins include, but are not limited to, propylene,butene-1, pentene-1, 4-methylpentene-1, pentene-1, hexene-1 andoctene-1, and preferably propylene, butene-1, hexene-1 and octene-1.

In one embodiment, the second ethylene-based polymer is selected from anethylene/alpha-olefin copolymer, a low density polyethylene (LDPE), ahigh density polyethylene (HDPE), or a combination thereof.

The second ethylene-based polymer may comprise a combination of two ormore embodiments as described herein.

In one embodiment, the first ethylene-based polymer is present in anamount from “greater than zero” to 30 weight percent, further from 1 to25 weight percent, further from 2 to 20 weight percent, based on the sumof the weight of first ethylene-based polymer and the secondethylene-based polymer.

In one embodiment, the first ethylene-based polymer is present in anamount greater than, or equal to, 20 weight percent, further greaterthan, or equal to, 50 weight percent, based on the sum of the weight offirst ethylene-based polymer and the second ethylene-based polymer.

In one embodiment, the first ethylene-based polymer is present in anamount from 1 to 95 weight percent, further from 5 to 95 weight percent,further from 10 to 90 weight percent, based on the sum of the weight offirst ethylene-based polymer and the second ethylene-based polymer.

In one embodiment, the first ethylene-based polymer has a melt index(I2) from 0.2 g/10 min to 0.9 g/10 min, further from 0.3 g/10 min to 0.9g/10 min (ASTM 2.16 kg/190° C.).

In one embodiment, the first ethylene-based polymer has b) a Mw(abs)versus I2 relationship: Mw(abs)<A×[(I2)^(B)], where A=5.00×10²(kg/mole)/(dg/min)^(B), and B=−0.40 (Mw(abs) by GPC method A).

In one embodiment, the first ethylene-based polymer has b) a Mw(abs)versus I2 relationship: Mw(abs)<A×[(I2)^(B)], where A=4.25×10²(kg/mole)/(dg/min)^(B), and B=−0.40 (Mw(abs) by GPC method A).

In one embodiment, the first ethylene-based polymer has a c) a MS versusI2 relationship: MS≥C×[(I2)^(D)], where C=14.5 cN/(dg/min)^(D), andD=−0.55 (Melt Strength=MS, 190° C.).

In one embodiment, the first ethylene-based polymer has a c) a MS versusI2 relationship: MS≥C×[(I2)^(D)], where C=15.5 cN/(dg/min)^(D), andD=−0.55 (Melt Strength=MS, 190° C.).

In one embodiment, the first ethylene-based polymer has a melt strengthgreater than, or equal to, 9.0 cN, at 190° C., further greater than, orequal to, 12.0 cN, at 190° C., further greater than, or equal to, 15.0cN, at 190° C.

In one embodiment, the first ethylene-based polymer has a Melt Strength(190° C.) from 10 to 40 cN, further from 15 to 30 cN.

In one embodiment, the first ethylene-based polymer has a “weightfraction (w) of molecular weight greater than 10⁶ g/mole, based on thetotal weight of polymer, as determined by GPC(abs), that meets thefollowing relationship: w<E×[(I2)^(F)], where E=0.110 (dg/min)^(−F), andF=−0.38 (GPC Method A).

In one embodiment, the first ethylene-based polymer is polymerized in atleast one tubular reactor. In a further embodiment, the firstethylene-based polymer is polymerized in a tubular reactor system thatdoes not comprise an autoclave reactor.

In one embodiment, the first ethylene-based polymer is selected from apolyethylene homopolymer or an ethylene-based interpolymer.

In one embodiment, in the first ethylene-based polymer is selected froma polyethylene homopolymer or an ethylene-based copolymer; and whereinthe comonomer of the ethylene-based copolymer is selected from a vinylacetate, an alkyl acrylate, carbon monoxide, an acrylic acid, acarboxylic acid-containing comonomer, an ionomer, a mono olefin, orselected from a vinyl acetate, an alkyl acrylate, acrylic acid, or amono olefin. In a further embodiment, the comonomer is present in anamount from 0.5 to 30 wt % comonomer, based on weight of copolymer.

In one embodiment, the first ethylene-based polymer is a LDPE.

In one embodiment, the first ethylene-based polymer has a density from0.910 to 0.940 g/cc (1 cc=1 cm³).

In one embodiment, the first ethylene-based polymer has a densitygreater than, or equal to, 0.912 g/cc, or greater than, or equal to,0.915 g/cc, or greater than, or equal to, 0.916 g/cc.

In one embodiment, the first ethylene-based polymer has a density lessthan, or equal to, 0.935 g/cc, or less than, or equal to, 0.930 g/cc, orless than, or equal to, 0.925 g/cc, or less than, or equal to, 0.920g/cc.

The first ethylene-based polymer may comprise a combination of two ormore embodiments as described herein.

An inventive composition may comprise a combination of two or moreembodiments as described herein.

The invention also provides an article comprising at least one componentformed from an inventive composition.

In one embodiment, the article is selected from coatings, films, foams,laminates, fibers, or tapes. In another embodiment, the article is afilm.

The invention also provides a film comprising at least one layer formedfrom an inventive composition.

In one embodiment, the film comprises at least two layers.

In one embodiment, the film has a MD shrink tension greater than 3.00psi.

An inventive article may comprise a combination of two or moreembodiments as described herein.

An inventive film may comprise a combination of two or more embodimentsas described herein

Polymerizations

For a high pressure, free radical initiated polymerization process, twobasic types of reactors are known. The first type is an agitatedautoclave vessel having one or more reaction zones (the autoclavereactor). The second type is a jacketed tube which has one or morereaction zones (the tubular reactor). The pressure in each autoclave andtubular reactor zone of the process is typically from 100 to 400, moretypically from 120 to 360, and even more typically from 150 to 320 MPa.The polymerization temperature in each tubular reactor zone of theprocess is typically from 100 to 400° C., more typically from 130 to360° C., and even more typically from 140 to 330° C.

The polymerization temperature in each autoclave reactor zone of theprocess is typically from 150 to 300° C., more typically from 165 to290° C., and even more typically from 180 to 280° C.

The high pressure process of the present invention to producepolyethylene homo or interpolymers, having the advantageous properties,as found in accordance with the invention, is preferably carried out ina tubular reactor having at least three reaction zones.

The first ethylene-based polymers with broad MWD are typically made atpolymerization conditions comprising one or more of the followingprocess elements:

-   -   Reduced operating pressure (versus maximum operating pressure of        reactor system).    -   Elevated polymerization temperatures: one or more autoclave zone        and/or one or more tubular reactor zone are operated at a        control or maximum peak temperature exceeding respectively 240        and 290° C.    -   Minimal three reaction zones of autoclave and/or tubular nature.    -   Selection of type and/or distribution of CTA over the reaction        zones to ensure broad MWD product.    -   Optional use of a bifunctional coupling and/or branching agent.

Initiators

The first ethylene-based polymer is formed by a free radicalpolymerization process. The type of free radical initiator to be used inthe present process is not critical, but preferably one of theinitiators applied should allow high temperature operation in the rangefrom 300° C. to 350° C. Free radical initiators that are generally usedinclude organic peroxides, such as peresters, perketals, peroxy ketones,percarbonates, and cyclic multifunctional peroxides. These organicperoxy initiators are used in conventional amounts, typically from 0.005to 0.2 wt % based on the weight of polymerizable monomers. Othersuitable initiators include azodicarboxylic esters, azodicarboxylicdinitriles and 1,1,2,2-tetramethylethane derivatives, and othercomponents capable of forming free radicals in the desired operatingtemperature range. Peroxides are typically injected as diluted solutionsin a suitable solvent, for example, in a hydrocarbon solvent.

In one embodiment, an initiator is added to at least one reaction zoneof the polymerization, and wherein the initiator has a “half-lifetemperature at one second” greater than 255° C., preferably greater than260° C. In a further embodiment, such initiators are used at a peakpolymerization temperature from 320° C. to 350° C. In a furtherembodiment, the initiator comprises at least one peroxide groupincorporated in a ring structure.

Examples of such initiators include, but are not limited to, TRIGONOX301 (3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxonaan) and TRIGONOX311 (3,3,5,7,7-pentamethyl-1,2,4-trioxepane), both available from AkzoNobel, and HMCH-4-AL (3,3,6,6,9,9-hexamethyl-1,2,4,5-tetroxonane)available from United Initiators. See also International PublicationNos. WO 02/14379 and WO 01/68723.

Chain Transfer Agents (CTA)

Chain transfer agents or telogens are used to control the melt index ina polymerization process. Chain transfer involves the termination ofgrowing polymer chains, thus limiting the ultimate molecular weight ofthe polymer material. Chain transfer agents are typically hydrogen atomdonors that will react with a growing polymer chain and stop thepolymerization reaction of the chain. These agents can be of manydifferent types, from saturated hydrocarbons or unsaturated hydrocarbonsto aldehydes, ketones or alcohols. By controlling the concentration ofthe selected chain transfer agent, one can control the length of polymerchains, and, hence the molecular weight, for example, the number averagemolecular weight, Mn. The melt flow index (MFI or I₂) of a polymer,which is related to Mn, is controlled in the same way.

The chain transfer agents used in the process of this invention include,but are not limited to, aliphatic and olefinic hydrocarbons, such aspentane, hexane, cyclohexane, propene, pentene or hexane; ketones suchas acetone, diethyl ketone or diamyl ketone; aldehydes such asformaldehyde or acetaldehyde; and saturated aliphatic aldehyde alcoholssuch as methanol, ethanol, propanol or butanol. The chain transfer agentmay also be a monomeric chain transfer agent. For example, see WO2012/057975, U.S. 61/579,067, and U.S. 61/664,956.

Differentiated CTA concentrations in the reaction zones can be used toachieve and to control the desired molecular weight distribution. Meansto differentiate the CTA concentration in reaction zones include amongothers methods described in WO2013/059042, WO2011/075465 andWO2012/044504.

A further way to influence the melt index includes the build up andcontrol, in the ethylene recycle streams, of incoming ethyleneimpurities, like methane and ethane, peroxide dissociation products,like tert-butanol, acetone, etc., and or solvent components used todilute the initiators. These ethylene impurities, peroxide dissociationproducts, and/or dilution solvent components can act as chain transferagents.

Monomer and Comonomers

The term ethylene interpolymer as used in the present description andthe claims refer to polymers of ethylene and one or more comonomers.Suitable comonomers to be used in the ethylene polymers of the presentinvention include, but are not limited to, ethylenically unsaturatedmonomers and especially C₃₋₂₀ alpha-olefins, carbon monoxide, vinylacetate, alkyl acrylates, or a bifunctional or higher functionalcomonomer (includes monomers with two or more monomeric groups).Typically comonomers can also act as chain transfer agents to somedegree. Those comonomers with high chain transfer activity aredesignated as monomeric CTAs.

Additives

An inventive composition may comprise one or more additives. Suitableadditives include stabilizers; fillers, such as organic or inorganicparticles, including clays, talc, titanium dioxide, zeolites, powderedmetals, organic or inorganic fibers, including carbon fibers, siliconnitride fibers, steel wire or mesh, and nylon or polyester cording,nano-sized particles, clays, and so forth; tackifiers, oil extenders,including paraffinic or napthelenic oils. An inventive composition maycomprise other polymer types.

Applications

The polymers of this invention may be employed in a variety ofconventional thermoplastic fabrication processes to produce usefularticles, including, but not limited to, monolayer and multilayer films;molded articles, such as blow molded, injection molded, or rotomoldedarticles; coatings; fibers; and woven or non-woven fabrics.

An inventive polymer may be used in a variety of films, including butnot limited to, extrusion coating, food packaging, consumer, industrial,agricultural (applications or films), lamination films, fresh cutproduce films, meat films, cheese films, candy films, clarity shrinkfilms, collation shrink films, stretch films, silage films, greenhousefilms, fumigation films, liner films, stretch hood, heavy duty shippingsacks, pet food, sandwich bags, sealants, and diaper backsheets.

An inventive polymer is also useful in other direct end-useapplications. An inventive polymer may be used for wire and cablecoating operations, in sheet extrusion for vacuum forming operations,and forming molded articles, including the use of injection molding,blow molding process, or rotomolding processes.

Other suitable applications for the inventive polymers include elasticfilms and fibers; soft touch goods, such as appliance handles; gasketsand profiles; auto interior parts and profiles; foam goods (both openand closed cell); impact modifiers for other thermoplastic polymers,such as high density polyethylene, or other olefin polymers; cap liners;and flooring.

Definitions

Unless stated to the contrary, implicit from the context, or customaryin the art, all parts and percents are based on weight and all testmethods are current as of the filing date of this disclosure.

The term “composition,” as used herein, refers to a mixture of materialswhich comprise the composition, as well as reaction products anddecomposition products formed from the materials of the composition.

The terms “blend” or “polymer blend,” as used, mean an intimate physicalmixture (that is, without reaction) of two or more polymers. A blend mayor may not be miscible (not phase separated at molecular level). A blendmay or may not be phase separated. A blend may or may not contain one ormore domain configurations, as determined from transmission electronspectroscopy, light scattering, x-ray scattering, and other methodsknown in the art. The blend may be effected by physically mixing the twoor more polymers on the macro level (for example, melt blending resinsor compounding) or the micro level (for example, simultaneous formingwithin the same reactor, or forming one polymer in the presence ofanother polymer).

The term “polymer” refers to a compound prepared by polymerizingmonomers, whether of the same or a different type. The generic termpolymer thus embraces the term homopolymer (which refers to polymersprepared from only one type of monomer with the understanding that traceamounts of impurities can be incorporated into the polymer structure),and the term “interpolymer” as defined infra. Trace amounts ofimpurities may be incorporated into and/or within a polymer.

The term “interpolymer” refers to polymers prepared by thepolymerization of at least two different types of monomers. The genericterm interpolymer includes copolymers (which refers to polymers preparedfrom two different monomers), and polymers prepared from more than twodifferent types of monomers.

The term “ethylene-based polymer” or “ethylene polymer” refers to apolymer that comprises a majority amount of polymerized ethylene basedon the weight of the polymer, and, optionally, may comprise at least onecomonomer.

The term “ethylene-based interpolymer” or “ethylene interpolymer” refersto an interpolymer that comprises a majority amount of polymerizedethylene based on the weight of the interpolymer, and comprises at leastone comonomer.

The term “ethylene-based copolymer” or “ethylene copolymer” refers to aninterpolymer that comprises a majority amount of polymerized ethylenebased on the weight of the copolymer, and only one comonomer (thus, onlytwo monomer types).

The terms “autoclave-based products” or “autoclaved-based polymers,” asused herein, refer to polymers prepared in a reactor system comprisingat least one autoclave reactor.

The phrase “high pressure, free-radical polymerization process,” as usedherein, refers to a free radical initiated polymerization carried out atan elevated pressure of at least 1000 bar (100 MPa).

The terms “comprising,” “including,” “having,” and their derivatives,are not intended to exclude the presence of any additional component,step or procedure, whether or not the same is specifically disclosed. Inorder to avoid any doubt, all compositions claimed through use of theterm “comprising” may include any additional additive, adjuvant, orcompound, whether polymeric or otherwise, unless stated to the contrary.In contrast, the term, “consisting essentially of” excludes from thescope of any succeeding recitation any other component, step orprocedure, excepting those that are not essential to operability. Theterm “consisting of” excludes any component, step or procedure notspecifically delineated or listed.

Test Methods

Density:

Samples for density measurement are prepared according to ASTM D 1928.Polymer samples are pressed at 190° C. and 30,000 psi (207 MPa) forthree minutes, and then at 21° C. and 207 MPa for one minute.Measurements are made within one hour of sample pressing using ASTMD792, Method B.

Melt Index:

Melt index, or I2=I₂, (grams/10 minutes or dg/min) is measured inaccordance with ASTM D 1238, Condition 190° C./2.16 kg. I₁₀ is measuredwith ASTM D 1238, Condition 190° C./10 kg.

Method A: Triple Detector Gel Permeation Chromatography (TDGPC):

High temperature 3Det-GPC analysis is performed on an ALLIANCE GPCV2000instrument (Waters Corp.) set at 145° C. The flow rate for the GPC is 1mL/min. The injection volume is 218.5 μL. The column set consists offour Mixed-A columns (20-μm particles; 7.5×300 mm; Polymer LaboratoriesLtd).

Detection is achieved by using an IR4 detector from PolymerChAR,equipped with a CH-sensor; a Wyatt Technology Dawn DSP MALS detector(Wyatt Technology Corp., Santa Barbara, Calif., USA), equipped with a30-mW argon-ion laser operating at λ=488 nm; and a Watersthree-capillary viscosity detector. The MALS detector is calibrated bymeasuring the scattering intensity of the TCB solvent. Normalization ofthe photodiodes is done by injecting SRM 1483, a high densitypolyethylene with weight-average molecular weight (Mw) of 32,100 g/moland polydispersity (MWD) of 1.11. A specific refractive index increment(dn/dc) of −0.104 mL/mg, for polyethylene in TCB, is used.

The conventional GPC calibration is done with 20 narrow PS standards(Polymer Laboratories Ltd.) with molecular weights in the range580-7,500,000 g/mol. The polystyrene standard peak molecular weights areconverted to polyethylene molecular weights using the followingequation:

M _(polyethylene) =A×(M _(polystyrene))^(B),

with A=0.39, B=1. The value of A is determined by using a linear highdensity polyethylene homopolymer (HDPE) with Mw of 115,000 g/mol. TheHDPE reference material is also used to calibrate the IR detector andviscometer by assuming 100% mass recovery and an intrinsic viscosity of1.873 dL/g.

The column calibration curve was obtained by fitting a first orderpolynomial to the respective polyethylene-equivalent calibration pointsobtained from the above Equation to the observed elution volumes.

Number, weight, and z-average molecular weights (GPC) were calculatedaccording to the following equations:

${\overset{\_}{Mn} = {{\frac{\sum\limits^{i}{Wf}_{i}}{\sum\limits^{i}\left( {{Wf}_{i}/M_{i}} \right)}\mspace{14mu} \overset{\_}{Mw}} = {{\frac{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}} \right)}{\sum\limits^{i}{Wf}_{i}}\mspace{14mu} \overset{\_}{Mz}} = \frac{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}^{2}} \right)}{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}} \right)}}}},$

where, Wf_(i) is the weight fraction of the i-th component and M_(i) isthe molecular weight of the i-th component. The molecular weightdistribution (MWD) was expressed as the ratio of the weight averagemolecular weight (Mw) to the number average molecular weight (Mn).

Distilled “Baker Analyzed” grade 1,2,4-trichlorobenzene (J. T. Baker,Deventer, The Netherlands), containing 200 ppm of2,6-di-tert-butyl-4-methylphenol (Merck, Hohenbrunn, Germany), is usedas the solvent for sample preparation, as well as for the 3Det-GPCexperiment. HDPE SRM 1483 is obtained from the U.S. National Instituteof Standards and Technology (Gaithersburg, Md., USA).

LDPE solutions are prepared by dissolving the samples under gentlestirring for three hours at 160° C. The PS standards are dissolved underthe same conditions for 30 minutes. The sample concentration for the3Det-GPC experiment is 1.5 mg/mL, and the polystyrene concentrations are0.2 mg/mL.

A MALS detector measures the scattered signal from polymers or particlesin a sample under different scattering angles 9. The basic lightscattering equation (from M. Anderson, B. Wittgren, K.-G. Wahlund, Anal.Chem. 75, 4279 (2003)) can be written as follows:

${\sqrt{\frac{Kc}{R_{\theta}}} = \sqrt{\frac{1}{M} + {\frac{16\pi^{2}}{3\lambda^{2}}\frac{1}{M}{Rg}^{2}{\sin^{2}\left( \frac{\theta}{2} \right)}}}},$

where R_(θ) is the excess Rayleigh ratio, K is an optical constant,which is, among other things, dependent on the specific refractive indexincrement (dn/dc), c is the concentration of the solute, M is themolecular weight, R_(g) is the radius of gyration, and λ is thewavelength of the incident light. Calculation of the molecular weightand radius of gyration from the light scattering data requireextrapolation to zero angle (see also P. J. Wyatt, Anal. Chim. Acta 272,1 (1993)). This is done by plotting (Kc/Re)^(1/2) as a function ofsin²(θ/2) in the so-called Debye plot. The molecular weight can becalculated from the intercept with the ordinate, and the radius ofgyration from the initial slope of the curve. The second virialcoefficient is assumed to be negligible. The intrinsic viscosity numbersare calculated from both the viscosity and concentration detectorsignals by taking the ratio of the specific viscosity and theconcentration at each elution slice.

ASTRA 4.72 (Wyatt Technology Corp.) software is used to collect thesignals from the IR detector, the viscometer, and the MALS detector, andto run the calculations.

The calculated molecular weights, e.g. Mw(abs), and molecular weightdistributions (e.g., Mw(abs)/Mn(abs)) are obtained using a lightscattering constant derived from one or more of the polyethylenestandards mentioned and a refractive index concentration coefficient,dn/dc, of 0.104. Generally, the mass detector response and the lightscattering constant should be determined from a linear standard with amolecular weight in excess of about 50,000 Daltons. The viscometercalibration can be accomplished using the methods described by themanufacturer, or alternatively, by using the published values ofsuitable linear standards such as Standard Reference Materials (SRM)1475a, 1482a, 1483, or 1484a. The chromatographic concentrations areassumed low enough to eliminate addressing2^(nd virial coefficient effects (concentration effects on molecular weight).)

The obtained MWD(abs) curve from TD-GPC is summarized with threecharacteristic parameters: Mw(abs), Mn(abs), and w, where w is definedas “weight fraction of molecular weight greater than 10⁶ g/mole, basedon the total weight of polymer, and as determined by GPC(abs).”

In equation form, the parameters are determined as follows. Numericalintegration from the table of “log M” and “dw/d log M” is typically donewith the trapezoidal rule:

${{{Mw}({abs})} = {\int_{- \infty}^{\infty}{M\frac{dw}{d\; \log \; M}d\; \log \; M}}},{{{Mn}({abs})} = \frac{1}{\int_{- \infty}^{\infty}{\frac{1}{M}\frac{dw}{d\; \log \; M}d\; \log \; M}}},{and}$$w = {\int_{6}^{\infty}{\frac{dw}{d\; \log \; M}d\; \log \; {M.}}}$

Method B: Triple Detector Gel Permeation Chromatography(TDGPC)—Conventional GPC Data

A Triple Detector Gel Permeation Chromatography (3D-GPC or TDGPC) systemconsisting of a Polymer Laboratories (now Agilent) high temperaturechromatograph Model 220, equipped with a 2-angle laser light scattering(LS) detector Model 2040 (Precision Detectors, now Agilent), an IR-4infra-red detector from Polymer Char (Valencia, Spain), and a4-capillary solution viscometer (DP) (Viscotek, now Malvern) was used.Data collection was performed using Polymer Char DM 100 data acquisitionbox and related software (Valencia, Spain). The system was also equippedwith an on-line solvent degassing device from Polymer Laboratories (nowAgilent).

High temperature GPC columns consisting of four 30 cm, 20 um mixed A LScolumns from Polymer Laboratories (now Agilent) were used. The samplecarousel compartment was operated at 140° C., and the column compartmentwas operated at 150° C. The samples were prepared at a concentration of0.1 grams of polymer in 50 milliliters of solvent. The chromatographicsolvent and the sample preparation solvent was 1,2,4-trichlorobenzene(TCB) containing 200 ppm of 2,6-di-tert-butyl-4methylphenol (BHT). Thesolvent was sparged with nitrogen. The polymer samples were gentlystirred at 160° C. for four hours. The injection volume was 200microliters. The flow rate through the GPC was set at 1.0 ml/minute.

Column calibration and sample molecular weight calculations wereperformed using Polymer Char “GPC One” software. Calibration of the GPCcolumns was performed with 21 narrow molecular weight distributionpolystyrene standards. The molecular weights of the polystyrenestandards ranged from 580 to 8,400,000 g/mol, and were arranged in 6“cocktail” mixtures, with at least a decade of separation between theindividual molecular weights.

The peak molecular weights of polystyrene standards were converted topolyethylene molecular weights using the following equation (asdescribed in Williams and Ward, J. Polym. Sci., Polym. Let., 6, 621(1968)):

M _(polyethylene) =A(M _(polystyrene))^(B),

here B has a value of 1.0, and the experimentally determined value of Ais around 0.38 to 0.44.

The column calibration curve was obtained by fitting a first orderpolynomial to the respective polyethylene-equivalent calibration pointsobtained from the above Equation to the observed elution volumes.

Number, weight, and z-average molecular weights were calculatedaccording to the following equations:

$\overset{\_}{Mn} = {{\frac{\sum\limits^{i}{Wf}_{i}}{\sum\limits^{i}\left( {{Wf}_{i}/M_{i}} \right)}\mspace{14mu} \overset{\_}{Mw}} = {{\frac{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}} \right)}{\sum\limits^{i}{Wf}_{i}}\mspace{14mu} \overset{\_}{Mz}} = \frac{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}^{2}} \right)}{\sum\limits^{i}\left( {{Wf}_{i}*M_{i}} \right)}}}$

Where, Wf_(i) is the weight fraction of the i-th component and M_(i) isthe molecular weight of the i-th component. The molecular weightdistribution (MWD) was expressed as the ratio of the weight averagemolecular weight (Mw) to the number average molecular weight (Mn).

The A value was determined by adjusting the A value in the Williams andWard Equation until Mw, the weight average molecular weight calculatedusing the above Equation, and the corresponding retention volumepolynomial agreed with the independently determined value of Mw obtainedin accordance with the linear homopolymer reference with known weightaverage molecular weight of 115,000 g/mol.

Melt Strength

Melt strength measurements are conducted on a Gottfert Rheotens 71.97(Göettfert Inc.; Rock Hill, S.C.) attached to a Gottfert Rheotester 2000capillary rheometer. A polymer melt is extruded through a capillary diewith a flat entrance angle (180 degrees) with a capillary diameter of2.0 mm and an aspect ratio (capillary length/capillary diameter) of 15.

After equilibrating the samples at 190° C. for 10 minutes, the piston isrun at a constant piston speed of 0.265 mm/second. The standard testtemperature is 190° C. The sample is drawn uniaxially to a set ofaccelerating nips located 100 mm below the die with an acceleration of2.4 mm/second². The tensile force is recorded as a function of thetake-up speed of the nip rolls. Melt strength is reported as the plateauforce (cN) before the strand broke. The following conditions are used inthe melt strength measurements: plunger speed=0.265 mm/second; wheelacceleration=2.4 mm/s²; capillary diameter=2.0 mm; capillary length=30mm; and barrel diameter=12 mm.

Nuclear Magnetic Resonance (¹³C NMR)

Samples were prepared by adding approximately “3 g of a 50/50 mixture oftetrachloroethane-d2/orthodichlorobenzene, containing 0.025 MCr(AcAc)₃,” to a “0.25 to 0.40 g polymer sample,” in a 10 mm NMR tube.Oxygen was removed from the sample by placing the open tubes in anitrogen environment for at least 45 minutes. The samples were thendissolved and homogenized by heating the tube, and its contents to 150°C., using a heating block and heat gun. Each dissolved sample wasvisually inspected to ensure homogeneity. Samples were thoroughly mixed,immediately prior to analysis, and were not allowed to cool beforeinsertion into the heated NMR sample holders.

All data were collected using a Bruker 400 MHz spectrometer. The datawas acquired using a six second pulse repetition delay, 90-degree flipangles, and inverse gated decoupling, with a sample temperature of 125°C. All measurements were made on non-spinning samples in locked mode.Samples were allowed to thermally equilibrate for seven minutes prior todata acquisition. The ¹³C NMR chemical shifts were internally referencedto the EEE triad at 30.0 ppm. The C6+ value was a direct measure of C6+branches in LDPE, where the long branches were not distinguished fromchain ends. The 32.2 ppm peak, representing the third carbon from theend of all chains or branches of six or more carbons, was used todetermine C6+ value.

Nuclear Magnetic Resonance (¹H NMR) Sample Preparation

The samples were prepared by adding approximately 130 mg of sample to“3.25 g of 50/50, by weight, tetrachlorethane-d2/perchloroethylene” with0.001 M Cr(AcAc)₃ in a NORELL 1001-7, 10 mm NMR tube. The samples werepurged by bubbling N2 through the solvent, via a pipette inserted intothe tube, for approximately five minutes, to prevent oxidation. Eachtube was capped, sealed with TEFLON tape, and then soaked at roomtemperature, overnight, to facilitate sample dissolution. The sampleswere kept in a N2 purge box, during storage, before, and afterpreparation, to minimize exposure to 02. The samples were heated andvortexed at 115° C. to ensure homogeneity.

Data Acquisition Parameters

The 1H NMR was performed on a Bruker AVANCE 400 MHz spectrometer,equipped with a Bruker Dual DUL high-temperature CryoProbe, and a sampletemperature of 120° C. Two experiments were run to obtain spectra, acontrol spectrum to quantitate the total polymer protons, and a doublepresaturation experiment, which suppressed the intense polymer backbonepeaks, and enabled high sensitivity spectra for quantitation of theend-groups. The control was run with ZG pulse, 4 scans, SWH 10,000 Hz,AQ 1.64 s, D1 14 s. The double presaturation experiment was run with amodified pulse sequence, TD 32768, 100 scans, DS 4, SWH 10,000 Hz, AQ1.64 s, D1 1 s, D13 13 s.

Data Analysis—1H NMR Calculations

The signal from residual 1H in TCE-d2 (at 6.0 ppm) was integrated, andset to a value of 100, and the integral from 3 to −0.5 ppm was used asthe signal from the whole polymer in the control experiment. For thepresaturation experiment, the TCE signal was also set to 100, and thecorresponding integrals for unsaturation (vinylene at about 5.40 to 5.60ppm, trisubstituted at about 5.16 to 5.35 ppm, vinyl at about 4.95 to5.15 ppm, and vinylidene at about 4.70 to 4.90 ppm) were obtained.

In the presaturation experiment spectrum, the regions for cis- andtrans-vinylene, trisubstituted, vinyl, and vinylidene were integrated.The integral of the whole polymer from the control experiment wasdivided by two to obtain a value representing X thousands of carbons(i.e., if the polymer integral=28000, this represents 14,000 carbons,and X=14).

The unsaturated group integrals, divided by the corresponding number ofprotons contributing to that integral, represent the moles of each typeof unsaturation per X thousand carbons. Dividing the moles of each typeof unsaturation by X, then gives moles unsaturated groups per 1000 molesof carbons.

Film Testing

The following physical properties were measured on the films asdescribed in the experimental section. Film thickness was measured usinga Measuretech instrument.

Total (Overall) Haze and Internal Haze: Internal haze and total hazewere measured according to ASTM D 1003-07. Internal haze was obtainedvia refractive index matching using mineral oil (1-2 teaspoons), whichwas applied as a coating on each surface of the film. A Hazegard Plus(BYK-Gardner USA; Columbia, Md.) was used for testing. For each test,five samples were examined, and an average reported. Sample dimensionswere “6 in×6 in.”

45° Gloss: ASTM D2457-08 (average of five film samples; each sample “10in×10 in”).

Clarity: ASTM D1746-09 (average of five film samples; each sample “10in×10 in”).

2% Secant Modulus-MD (machine direction) and CD (cross direction): ASTMD882-10 (average of five film samples in each direction; each sample “1in×6 in”).

MD and CD Elmendorf Tear Strength: ASTM D1922-09 (average of 15 filmsamples in each direction; each sample “3 in×2.5 in” half moon shape).

MD and CD Tensile Strength: ASTM D882-10 (average of five film samplesin each direction; each sample “1 in×6 in”).

Dart Impact Strength: ASTM D1709-09 (minimum of 20 drops to achieve a50% failure; typically ten “10 in×36 in” strips).

Puncture Strength: Puncture was measured on an INSTRON Model 4201 withSINTECH TESTWORKS SOFTWARE Version 3.10. The specimen size was “6 in×6in,” and four measurements were made to determine an average puncturevalue. The film was conditioned for 40 hours after film production, andat least 24 hours in an ASTM controlled laboratory (23° C. and 50%relative humidity). A “100 lb” load cell was used with a round specimenholder of 4 inch diameter. The puncture probe is a “½ inch diameter”polished stainless steel ball (on a 2.5″ rod) with a “7.5 inch maximumtravel length.”

There was no gauge length, and the probe was as close as possible to,but not touching, the specimen. The probe was set by raising the probeuntil it touched the specimen. Then the probe was gradually lowered,until it was not touching the specimen. Then the crosshead was set atzero. Considering the maximum travel distance, the distance would beapproximately 0.10 inch. The crosshead speed was 10 inches/minute. Thethickness was measured in the middle of the specimen. The thickness ofthe film, the distance the crosshead traveled, and the peak load wereused to determine the puncture by the software. The puncture probe wascleaned using a “KIM-WIPE” after each specimen.

Shrink Tension: Shrink tension was measured according to the methoddescribed in Y. Jin, T. Hermel-Davidock, T. Karjala, M. Demirors, J.Wang, E. Leyva, and D. Allen, “Shrink Force Measurement of Low ShrinkForce Films”, SPE ANTEC Proceedings, p. 1264 (2008). The shrink tensionof film samples was measured through a temperature ramp test that wasconducted on an RSA-III Dynamic Mechanical Analyzer (TA Instruments; NewCastle, Del.) with a film fixture. Film specimens of “12.7 mm wide” and“63.5 mm long” were die cut from the film sample, either in the machinedirection (MD) or the cross direction (CD), for testing. The filmthickness was measured by a Mitutoyo Absolute digimatic indicator (ModelC112CEXB). This indicator had a maximum measurement range of 12.7 mm,with a resolution of 0.001 mm. The average of three thicknessmeasurements, at different locations on each film specimen, and thewidth of the specimen, were used to calculate the film's cross sectionalarea (A), in which “A=Width×Thickness” of the film specimen that wasused in shrink film testing. A standard film tension fixture from TAInstruments was used for the measurement. The oven of the RSA-III wasequilibrated at 25° C., for at least 30 minutes, prior to zeroing thegap and the axial force. The initial gap was set to 20 mm.

The film specimen was then attached onto both the upper and the lowerfixtures. Typically, measurements for MD only require one ply film.Because the shrink tension in the CD direction is typically low, two orfour plies of films are stacked together for each measurement to improvethe signal-to-noise ratio. In such a case, the film thickness is the sumof all of the plies. In this work, a single ply was used in the MDdirection and two plies were used in the CD direction. After the filmreached the initial temperature of 25° C., the upper fixture wasmanually raised or lowered slightly to obtain an axial force of −1.0 g.This was to ensure that no buckling or excessive stretching of the filmoccurred at the beginning of the test. Then the test was started. Aconstant fixture gap was maintained during the entire measurement.

The temperature ramp started at a rate of 90° C./min, from 25° C. to 80°C., followed by a rate of 20° C./min, from 80° C. to 160° C. During theramp from 80° C. to 160° C., as the film shrunk, the shrink force,measured by the force transducer, was recorded as a function oftemperature for further analysis. The difference between the “peakforce” and the “baseline value before the onset of the shrink forcepeak” is considered the shrink force (F) of the film. The shrink tensionof the film is the ratio of the shrink force (F) to the initial crosssectional area (A) of the film.

For the MD Shrink Tension, three film samples were tested, and anaverage reported.

For the CD Shrink Tension, three film samples were tested, and anaverage reported.

EXPERIMENTAL First Ethylene-Based Polymer

IE1: The polymerization was carried out in tubular reactor with threereaction zones. In each reaction zone, pressurized water was used forcooling and/or heating the reaction medium, by circulating this waterthrough the jacket of the reactor. The inlet-pressure was 2100 bar, andthe pressure drop over the whole tubular reactor system was about 300bars. Each reaction zone had one inlet and one outlet. Each inlet streamconsisted of the outlet stream from the previous reaction zone and/or anadded ethylene-rich feed stream. The ethylene was supplied according toa specification, which allowed a trace amount (maximum of 5 mol ppm) ofacetylene in the ethylene. The non-converted ethylene, and other gaseouscomponents in the reactor outlet, were recycled through a high pressureand a low pressure recycle system, and were compressed and distributedthrough a booster, a primary compressor system and a hyper (secondary)compressor system, according to the flow scheme shown in FIG. 1B. Asseen in FIG. 1B, both discharge streams (2 and 3) of the primarycompressor were sent to the reactor front feed stream 5.

Organic peroxides were fed into each reaction zone (see Table 1).Propionaldehyde was used as a chain transfer agent, and it was presentin each reaction zone inlet originating from the low pressure and highpressure recycle flows (13 and 15), as well as from freshly injected CTAmake-up stream 7 and/or stream 6. The polymer was made at a melt indexof 0.58 g/10 min.

After reaching the first peak temperature (maximum temperature) inreaction zone 1, the reaction medium was cooled with the help of thepressurized water. At the outlet of the reaction zone 1, the reactionmedium was further cooled by injecting a fresh, cold, ethylene-rich feedstream (20), and the reaction was re-initiated by feeding an organicperoxide. This process was repeated at the end of the second reactionzone, to enable further polymerization in the third reaction zone. Thepolymer was extruded and pelletized (about 30 pellets per gram), using a“single screw” extruder system at a melt temperature around 230-250° C.The weight ratio of the ethylene-rich feed streams (9:20:21) to thethree reaction zones was 1.00:0.76:0.24. The R2 and R3 values eachapproached infinity. The R values are calculated according toInternational Publication WO 2013/059042 (International PatentApplication PCT/US12/059469 filed Oct. 10, 2012). Rn (n=reaction zonenumber, n>1) is the ratio of “mass fraction of fresh ethylene fed to thefirst reaction zone (RZ1)” to “mass fraction of fresh ethylene fed tothe nth reaction zone (RZn)” is (Rn=RZ1/RZn). The internal processvelocity was approximately 12.5, 9 and 11 m/sec, respectively, for thefirst, second and third reaction zone. In this inventive example, theweight ratio of the CTA make-up streams 7 and 6 was 2. Additionalinformation can be found in Tables 2 and 3.

Example IE2

The polymerization was carried out in tubular reactor with threereaction zones, as discussed above, according to Example IE1 (see FIG.1B). The weight ratio of the ethylene-rich feed streams (9:20:21) to thethree reaction zones was 1.00:0.76:0.24. The polymer was made at a meltindex of 0.37 g/10 min. The R2 and R3 values each approached infinity(∞). In this inventive example, the weight ratio of the CTA make-upstreams 7 and 6 was 1.35. Additional information can be found in Tables2 and 3. The CTA was propionaldehyde (PA).

In summary, to achieve tubular resins with high melt strength suitableas blend component in extrusion coating compositions, typically togetherwith a low or lower melt strength component, the polymerizationconditions need to be selected and balanced; for example, as discussedabove. Important process parameters include maximum polymerizationtemperatures, inlet reactor pressure, conversion level, and the type,level and distribution of the chain transfer agent.

Polymer properties (IE1, IE2 and other polymers) are shown in Tables 4and 5.

TABLE 1 Initiators Initiator Abbreviation tert-Butyl peroxy-2-ethylhexanoate TBPO Di-tert-butyl peroxide DTBP 3,6,9-triethyl3,6,9-trimethyl 1,4,7-peroxonane TETMP

TABLE 2 Pressure and Temperature Conditions (First Ethylene-basedPolymers) reiniti- reiniti- ation ation temp. temp. 1st 2nd 3rd Inlet-Start- 2nd 3rd Peak Peak Peak LDPE pressure/ temp./ zone/ zone/ temp./temp./ temp./ Exs. Type bar ° C. ° C. ° C. ° C. ° C. ° C. IE1 Inv 2100140 169 243 330 325 299 IE2 Inv 2100 140 173 243 327 323 299

TABLE 3 Additional Information (First Ethylene-based Polymers) R2 andEthylene LDPE I2 R3 Conver- Exs. Peroxides CTA dg/min⁻¹ Value sion % IE1TBPO/DTBP/TETMP PA 0.58 ∞ 29.3 IE2 TBPO/DTBP/TETMP PA 0.37 ∞ 27.6

TABLE 4 Polymer Properties Mw Melt Fraction with I2 Density Mw(abs)(abs)/M Strength MW above Mw(abs)/ LDPE Type* (dg/min) (g/cc) (kg/mol)^(t) n(abs) ^(t) (cN) 1 × 10⁶ g/mol ^(t) Mw(GPC) ^(t) LDPE 662I** CE, AC0.38 0.9182 872 46.1 30.0 0.202 3.54 LD310E** CE, tub 0.7 0.9231 144 8.314.0 0.018 1.51 AGILITY 1001** CE, tub 0.64 0.9206 204 15.6 11.3 0.0321.81 LDPE 132I** CE, tub 0.25 0.9209 273 15.3 17.3 0.052 2.14 IE1 IE,tub 0.58 0.9180 287 16.6 26.8 0.066 1.92 IE2 IE, tub 0.37 0.9180 29717.5 29.9 0.072 2.01 *CE: Comparative; IE: Inventive; AC:Autoclave-based; tub: Tubular **Commercial Polymers available from TheDow Chemical Company.

^(t) All MWD metrics in this table obtained from GPC Method A.

TABLE 5 Polymer Properties Melt Fraction with I2 Mw(abs) Strength Mabove A × [(I2)^(B)] C × [(I2)^(D)] LDPE (dg/min) (kg/mol)t (cN) 1.10⁶g/mol^(t) (kg/mol)^(a) (cN)^(b) 662I 0.38 872 30.0 0.202 736 23.0 LD310E0.7 144 14.0 0.018 577 16.4 AGILITY 1001 0.64 204 11.3 0.032 613 17.9LDPE 132I 0.25 273 17.3 0.052 871 28.9 IE1 0.58 287 26.8 0.066 622 18.2IE2 0.37 297 29.9 0.072 744 23.3 ^(a)Mw(abs) < A × [(I2)^(B)], where A =5.00 × 10² (kg/mole)/(dg/min)^(B) , and B = −0.40 [Mw(abs), GPC MethodA]. ^(b)MS ≥ C × [(I2)^(D)], where C = 13.5 cN/(dg/min)^(D), and D =−0.55 [Melt Strength = MS, ° C.]. ^(t)All MWD metrics in this tableobtained from GPC Method A.

Table 6 contains the branches per 1000 C as measured by ¹³C NMR. TheseLDPE polymers contain amyl, or C5 branches, which are not contained insubstantially linear polyethylenes such as AFFINITY PolyolefinPlastomers, or Ziegler-Natta catalyzed LLDPE, such as DOWLEXPolyethylene Resins, both produced by The Dow Chemical Company. EachLDPE shown in Table 6 contains greater than, or equal to, 2.0 amylgroups (branches) per 1000 carbon atoms. Table 7 contains unsaturationresults by ¹H NMR.

TABLE 6 Branching Results in branches per 1000 C by ¹³C NMR of InventiveExamples and Comparative Examples. 1,3 C2 on diethyl Quat C1 branchesCarbon C4 C5 C6+ IE1 ND 4.51 1.82 7.26 2.63 3.8 IE2 ND 4.55 1.83 7.302.16 3.5 AFFINITY PL 1880 ND ND ND ND ND 19.5* DOWLEX 2045G ND ND ND NDND 11.4* ND = not detected. *The values in the C6+ column for the DOWLEXand AFFINITY samples represent C6 branches from octene only, and do notinclude chain ends.

TABLE 7 Unsaturation Results by ¹H NMR cis and vinyli- total vinyl/trans/ trisub/ dene/ unsaturation/ 1000C 1000C 1000C 1000C 1000C IE10.046 0.148 0.083 0.247 0.52 IE2 0.048 0.137 0.075 0.246 0.51 AFFINITYPL 1880 0.040 0.064 0.123 0.043 0.270 DOWLEX 2045G 0.283 0.049 0.0420.055 0.430

Formulations

Blown films were made, and physical properties measured, with differentLDPEs and one LLDPE, LLDPE1 (DOWLEX 2045G). LLDPE1 had a 1.0 melt index(MI or 12), and a 0.920 g/cc density. Films were made at 5 wt %, 10 wt%, 20 wt %, 50 wt % and 80 wt % of the respective LDPE, based on theweight of the LDPE and LLDPE1.

Each formulation was compounded on a MAGUIRE gravimetric blender. Apolymer processing aid (PPA), DYNAMAR FX-5920A, was added to eachformulation. The PPA was added at 1 wt % of masterbatch, based on thetotal weight of the weight of the formulation. The PPA masterbatch(Ingenia AC-01-01, available from Ingenia Polymers) contained 8 wt % ofDYNAMAR FX-5920A in a polyethylene carrier. This amounts to 800 ppm PPAin the polymer.

LLDPE1 was also used as the LLDPE in the films made at maximum output.Maximum output was determined on samples made with the followingcomponents: 95 wt % DOWLEX 2045G and 5 wt % LDPE; 90 wt % DOWLEX 2045Gand 10 wt % LDPE; and 80 wt % DOWLEX 2045G and 20 wt % LDPE.

Production of Blown Films

The monolayer blown films were made on an “8 inch die” with apolyethylene “Davis Standard Barrier II screw.” External cooling by anair ring and internal bubble cooling were used. General blown filmparameters, used to produce each blown film, are shown in Table 8. Thetemperatures are the temperatures closest to the pellet hopper (Barrel1), and in increasing order, as the polymer was extruded through thedie. The films at the standard rates were run at 250 lb/hr.

TABLE 8 Blown film fabrication conditions for films. Blow up ratio (BUR)2.5 Nominal Film thickness 2.0 Die gap (mil) 70 Air temperature (° F.)45 Temperature profile (° F.) Barrel 1 375 Barrel 2 420 Barrel 3 390Barrel 4 375 Barrel 5 375 Screen Temperature 450 Adapter 450 Block 450Lower Die 450 Inner Die 450 Upper Die 450

Production of Films for Determination of Maximum Output Rate of BlownFilm

Film samples were made at a controlled rate and at a maximum rate. Thecontrolled rate was 250 lb/hr, which equals a specific output rate of10.0 lb/hr/inch of die circumference. The die diameter used for themaximum output trials was an 8 inch die, so that for the controlledrate, as an example, the conversion between “lb/hr” and “lb/hr/inch” ofdie circumference, is shown below. Similarly, such an equation can beused for other rates, such as the maximum rate, by substituting themaximum rate in the equation below to determine the “lb/hr/inch” of diecircumference.

Specific Output=(250 Lb/Hr)/(8 inch*π)=10 Lb/Hr/Inch of DieCircumference

The maximum output rate for a given sample was determined by increasingthe output rate to the point where bubble stability was the limitingfactor. The extruder profile was maintained for both samples (standardrate and maximum rate), however the melt temperature was higher for themaximum rate samples, due to the increased shear rate with higher motorspeed (rpm, revolutions per minute). The bubble stability at maximumoutput rate was determined by taking the bubble to the point where itwould not stay seated in the air ring. At that point, the rate wasreduced to where the bubble was reseated (maximum output rate) in theair ring, and then a sample was collected. The cooling on the bubble wasadjusted by adjusting the air ring and maintaining the bubble. Thisprocess determined the maximum output rate while maintaining bubblestability.

The film results are summarized in Tables 9-16. Table 9 shows filmresults at standard rate with Film #1 being 100% LLDPE1, and Films #2-6being 95% LLDPE1/5% LDPE. Film #2, containing IE1 and Film #3 containingIE2, show advantages of good optics (low haze, and high gloss andclarity), MD tear (high), dart drop impact (high), and secant modulus(high). These properties are important for a variety of films with thedesirable properties of good optics and mechanical properties. TheseLDPEs enable the potential for down-gauging, or lowering of the filmthickness, while still retaining good mechanical properties. Table 10shows film results at maximum rate with Film #7 being 100% LLDPE1, andFilms #8-12 being 95% LLDPE1/5% LDPE. These films show advantages, asseen in Table 9 at standard rate. Additionally, compositions containingIE1 and IE2 show improvement in film output rates from 0.5-3.2% overcompositions containing the other LDPEs even at this low level of 5 wt %addition. The % increase in maximum output, as shown in Table 10, wascalculated as, for example for IE1:

% Increase in Output Due to IE1 as Compared to Reference LDPE=

(Maximum Output Blend with IE1−Maximum Output Blend with ReferenceLDPE)×100.

Maximum Output Blend with Reference LDPE

Table 11 contains results for 10% LDPE added to LLDPE1 for Films #13-17,and Table 12 contains results for 10% LDPE added to LLDPE1 for Films#18-22, made at maximum rate. These results show films advantagessimilar to those seen at 5% LDPE (good optics, MD tear, dart dropimpact, and secant modulus). Additionally, the maximum rate increasesover the reference LDPEs range up to 8.4%, as shown in Table 12.

Table 13 shows results for 80% LLDPE/20% LDPE at standard rates, andTable 14 shows results for 20% LDPE/80% LLDPE1 at maximum rates. Theseresults show properties similar to the lower % LDPE blends, butadditionally, at maximum rates, good shrink tension is found for theinventive compositions. The maximum output rates as compared to otherLDPEs are excellent at up to a 44% improvement. Although the autoclaveLDPE 662I does have good output rates, it suffers from poorer optics andpuncture. These very substantial differences in output are novel for theinventive compositions, and will translate, on larger blown film lines,to likely even more differentiation and larger gains in the speed atwhich blown films can be produced, leading to cost savings for theproducer. Additionally, key film property advantages are maintained.

Table 15 and 16 show results at 50% LDPE and 80% LDPE, respectively.Maximum output was not measured on these samples, but it is expectedthat the output of IE1 and IE2 would be very good and generally betterthan the comparative examples. Again, the optics, as compared to theautoclave LDPE 662I, are much improved, with retention of other filmproperties.

FIG. 2 shows the maximum output for the different LDPEs in LLDPE1, at0%, 5%, 10%, and 20% LDPE, and the differentiation and advantage of IE1and IE2, as compared to other LDPEs. FIG. 3 shows the MD shrink tensionfor films made at standard output for the different LDPEs in LLDPE1, at0%, 5%, 10%, and 20% LDPE, and the differentiation and advantage of IE1and IE2 as compared to other LDPEs.

TABLE 9 Film properties of 100% LLDPE1; and 95% LLDPE1/5% LDPE Films#1-6 made at 2 mil at a standard (std.) rate of 250 lb/hr (8″ die). Film1 2 3 4 5 6 Component 1 — IE1 IE2 AGILITY LDPE LDPE (First Polymer) 1001662I 132I Wt % Component 1 0 5 5 5 5 5 Melt Index Component 1 — 0.580.37 0.64 0.38 0.25 Component 2 LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1LLDPE1 (Second Polymer) Wt % Component 2 100 95 95 95 95 95 Blown FilmRate Std. Std. Std. Std. Std. Std. Haze (%) 16.8 11.1 10.6 9.8 10.4 9.4Haze, Internal (%) 5.9 4.3 4.0 4.4 4.6 4.0 45 Degree Gloss (%) 48.8 61.361.6 68.2 64.1 67.4 Clarity (%) 97.3 98.0 97.2 99.0 96.1 99.0 MD Tear(g) 874 822 809 735 774 797 CD Tear (g) 934 957 1,027 975 1,008 1,023Normalized MD Tear (g/mil) 454 422 404 379 378 392 Normalized CD Tear(g/mil) 489 484 517 504 493 500 Dart Drop Impact (g) 388 343 322 334 283302 Puncture (ft-lbf/in³) 278 269 254 264 271 275 2% MD Secant Modulus(kpsi) 37.7 38.5 38.8 35.6 36.9 36.7 2% CD Secant Modulus (kpsi) 42.542.6 42.8 40.2 41.7 39.7 MD Shrink Tension (psi) 3.29 5.50 4.70 6.044.46 5.99 CD Shrink Tension (psi) 0.43 0.43 0.70 0.54 0.60 0.70Thickness (mil) 1.96 2.05 2.06 1.83 1.97 2.01 Frost Line Height (inches)40 35 35 35 35 35 Melt Temperature (° F.) 443 440 440 439 439 440 RateOutput (lb/hr) 253 251 247 251 247 250 Rate Output (lb/hr/in) 10.1 10.09.8 10.0 9.8 9.9 Screen Pressure (psi) 3,550 3,630 3,590 3,620 3,5903,610

TABLE 10 Film properties of 100% LLDPE1; and 95% LLDPE1/5% LDPE Films#0-12 made at 2 mil at maximum rates (8″ die). Film 7 8 9 10 11 12Component 1 — IE1 IE2 AGILITY LDPE LDPE (First Polymer) 1001 662I 132IWt % Component 1 0 5 5 5 5 5 Melt Index Component 1 — 0.58 0.37 0.640.38 0.25 Component 2 LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 (SecondPolymer) Wt % Component 2 100 95 95 95 95 95 Haze (%) 29.5 17.6 14.913.2 15.2 14.6 Internal Haze (%) 5.7 4.6 4.8 4.8 5.9 6.0 45 Degree Gloss(%) 27.1 40.4 49.4 54.1 46.9 50.9 Clarity (%) 92.7 96.9 96.8 98.4 96.198.2 MD Tear (g) 975 834 711 830 891 820 CD Tear (g) 1,089 1,051 917 9811,135 1,148 Normalized MD Tear (g/mil) 442 401 380 422 407 373Normalized CD Tear (g/mil) 503 509 492 497 524 526 Dart Drop Impact (g)379 352 313 334 322 319 Puncture (ft-lbf/in³) 281 274 255 286 271 257 2%MD Secant Modulus (kpsi) 37.2 39.5 39.8 33.8 34.8 39.1 2% CD SecantModulus (kpsi) 45.0 41.8 44.8 39.3 43.5 41.6 MD Shrink Tension (psi)1.48 3.15 5.32 4.19 4.04 3.70 CD Shrink Tension (psi) 0.29 0.49 0.500.42 0.43 0.44 Thickness (mil) 1.89 1.93 2.07 2.04 2.06 2.16 Frost LineHeight (inches) 70 75 75 75 75 75 Melt Temperature (° F.) 451 457 458457 457 456 Rate Output (lb/hr) 329 380 387 378 375 376 Rate Output(lb/hr/in) 13.1 15.1 15.4 15.0 14.9 15.0 % Increase of Maximum Rate 0.51.3 1.1 IE1 over given LDPE % Increase of Maximum Rate 2.4 3.2 2.9 IE2over given LDPE % Increase of Maximum Rate 16 18 15 14 14 over LLDPE1Screen Pressure (psi) 4,150 4,290 4,420 4,400 4,290 4,420

TABLE 11 Film properties of 90% LLDPE1/10% LDPE Films #13-17 made at 2mil at a standard (std.) rate of 250 lb/hr (8″ die). Film 13 14 15 16 17Component 1 (First Polymer) IE1 IE2 AGILITY LDPE LDPE 1001 662I 132I Wt% Component 1 10 10 10 10 10 Melt Index Component 1 0.58 0.37 0.64 0.380.25 Component 2 (Second Polymer) LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt% Component 2 90 90 90 90 90 Blown Film Rate Std. Std. Std. Std. Std.Haze (%) 9.2 9.7 8.7 10.6 8.3 Haze, Internal (%) 3.5 3.3 4.0 4.0 3.4 45Degree Gloss (%) 66.9 63.2 68.9 59.7 68.4 Clarity (%) 97.4 95.7 98.993.0 98.6 MD Tear (g) 639 575 580 542 590 CD Tear (g) 993 1,081 1,0581,035 1,077 Normalized MD Tear (g/mil) 316 287 296 276 295 Normalized CDTear (g/mil) 488 543 539 515 545 Dart Drop Impact (g) 337 313 301 274250 Puncture (ft-lbf/in³) 249 267 244 261 266 2% MD Secant Modulus(kpsi) 37.7 36.7 30.2 30.1 29.2 2% CD Secant Modulus (kpsi) 42.3 41.333.6 36.2 34.0 MD Shrink Tension (psi) 6.08 7.42 5.66 5.91 5.42 CDShrink Tension (psi) 0.36 0.64 0.51 0.63 0.26 Thickness (mil) 2.02 2.051.89 2.00 1.97 Frost Line Height (inches) 35 35 35 35 35 MeltTemperature (° F.) 440 439 441 439 440 Rate Output (lb/hr) 251 250 250252 248 Rate Output (lb/hr/in) 10.0 9.9 9.9 10.0 9.9 Screen Pressure(psi) 3,620 3,740 3,540 3,740 3,660

TABLE 12 Film properties of 90% LLDPE1/10% LDPE Films #18-22 made at 2mil at maximum rates (8″ die). Film 18 19 20 21 22 Component 1 (FirstPolymer) IE1 IE2 AGILITY LDPE LDPE 1001 662I 132I Wt % Component 1 10 1010 10 10 Melt Index Component 1 0.58 0.37 0.64 0.38 0.25 Component 2(Second Polymer) LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt % Component 2 9090 90 90 90 Haze (%) 13.5 12.7 10.6 13.1 12.2 Internal Haze (%) 3.8 3.94.7 4.4 4.0 45 Degree Gloss (%) 49.6 50.1 61.7 53.3 54.3 Clarity (%)96.8 96.1 98.3 94.0 98.2 MD Tear (g) 720 666 628 588 673 CD Tear (g)1,086 1,145 1,103 1,045 1,092 Normalized MD Tear (g/mil) 358 317 309 298338 Normalized CD Tear (g/mil) 549 551 550 524 545 Dart Drop Impact (g)304 313 274 259 277 Puncture (ft-lbf/in³) 255 235 221 245 251 2% MDSecant Modulus (kpsi) 36.9 33.0 32.2 37.7 33.0 2% CD Secant Modulus(kpsi) 45.1 38.4 35.6 31.3 38.6 MD Shrink Tension (psi) 6.03 5.73 5.725.02 5.25 CD Shrink Tension (psi) 0.52 0.76 0.32 0.23 0.50 Thickness(mil) 2.03 1.82 1.83 1.98 1.86 Frost Line Height (inches) 84 85 80 80 80Melt Temperature (° F.) 458 461 459 460 461 Rate Output (lb/hr) 402 415383 403 392 Rate Output (lb/hr/in) 16.0 16.5 15.2 16.0 15.6 % Increaseof Maximum Rate IE1 5.0 −0.2 2.6 over given LDPE % Increase of MaximumRate IE2 8.4 3.0 5.9 over given LDPE % Increase of Maximum Rate 22 26 1622 19 over LLDPE1 Screen Pressure (psi) 4,480 4,600 4,270 4,450 4,390

TABLE 13 Film properties of 80% LLDPE1/20% LDPE Films #23-27 made at 2mil at a standard (std.) rate of 250 lb/hr (8″ die). Film 23 24 25 26 27Component 1 (First Polymer) IE1 IE2 AGILITY LDPE LDPE 1001 662I 132I Wt% Component 1 20 20 20 20 20 Melt Index Component 1 0.58 0.37 0.64 0.380.25 Component 2 (Second Polymer) LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt% Component 2 80 80 80 80 80 Blown Film Rate Std. Std. Std. Std. Std.Haze (%) 9.3 12.8 7.2 15.3 8.2 Haze, Internal (%) 2.9 3.3 3.3 2.7 2.6 45Degree Gloss (%) 61.5 48.9 72.6 44.4 65.4 Clarity (%) 92.9 85.6 98.382.3 96.2 MD Tear (g) 400 357 429 408 396 CD Tear (g) 1,060 1,065 1,2251,006 1,186 Normalized MD Tear (g/mil) 200 182 216 208 201 Normalized CDTear (g/mil) 525 540 611 509 593 Dart Drop Impact (g) 214 226 220 244241 Puncture (ft-lbf/in³) 212 224 236 209 222 2% MD Secant Modulus(kpsi) 30.9 30.2 29.6 29.7 30.8 2% CD Secant Modulus (kpsi) 35.6 35.732.8 37.2 36.4 MD Shrink Tension (psi) 11.32 12.66 9.29 7.05 11.53 CDShrink Tension (psi) 0.49 0.34 0.59 0.41 0.65 Thickness (mil) 1.99 1.952.08 1.96 2.02 Frost Line Height (inches) 35 35 35 35 35 MeltTemperature (° F.) 439 440 441 441 440 Rate Output (lb/hr) 252 252 251251 250 Rate Output (lb/hr/in) 10.0 10.0 10.0 10.0 9.9 Screen Pressure(psi) 3,660 3,650 3,580 3,730 3,720

TABLE 14 Film properties of 80% LLDPE1/20% LDPE Films #28-32 made at 2mil at maximum rates (8″ die). Film 28 29 30 31 32 Component 1 (FirstPolymer) IE1 IE2 AGILITY LDPE LDPE 1001 662I 132I Wt % Component 1 20 2020 20 20 Melt Index Component 1 0.58 0.37 0.64 0.38 0.25 Component 2(Second Polymer) LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt % Component 2 8080 80 80 80 Haze (%) 10.5 14.1 12.0 15.5 11.6 Internal Haze (%) 3.2 3.34.8 3.4 3.5 45 Degree Gloss (%) 56.3 44.7 54.9 40.9 55.7 Clarity (%)93.5 88.1 98.0 83.4 96.6 MD Tear (g) 430 445 508 420 489 CD Tear (g)1,105 1,031 991 1,015 1,185 Normalized MD Tear (g/mil) 216 228 249 218236 Normalized CD Tear (g/mil) 555 514 492 505 576 Dart Drop Impact (g)244 238 238 244 280 Puncture (ft-lbf/in³) 216 216 216 198 224 2% MDSecant Modulus (kpsi) 30.9 28.0 30.9 29.9 32.7 2% CD Secant Modulus(kpsi) 34.8 34.6 35.9 36.2 37.3 MD Shrink Tension (psi) 10.33 10.97 7.0512.33 8.21 CD Shrink Tension (psi) 0.42 0.46 0.41 0.46 0.38 Thickness(mil) 2.04 2.01 2.10 1.96 2.05 Frost Line Height (inches) 85 85 85 85 85Melt Temperature (° F.) 475 480 457 482 464 Rate Output (lb/hr) 541 581405 577 443 Rate Output (lb/hr/in) 21.5 23.1 16.1 23.0 17.6 % Increaseof Maximum Rate IE1 33.6 −0.6 22.1 over given LDPE % Increase of MaximumRate IE2 43.5 0.3 31.2 over given LDPE % Increase of Maximum Rate 64 7723 76 35 over LLDPE1 Screen Pressure (psi) 4,990 5,160 4,310 5,200 4,610

TABLE 15 Film properties of 50% LLDPE1/50% LDPE Films #33-37 made at 2mil at a standard (std.) rate of 250 lb/hr (8″ die). Film 33 34 35 36 37Component 1 (First Polymer) IE1 IE2 AGILITY LDPE LDPE 1001 662I 132I Wt% Component 1 50 50 50 50 50 Melt Index Component 1 0.58 0.37 0.64 0.380.25 Component 2 LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt % Component 2 5050 50 50 50 Blown Film Rate Std. Std. Std. Std. Std. Haze (%) 18.9 23.99.5 31.9 13.0 Haze, Internal (%) 3.1 2.1 2.3 2.0 1.7 45 Degree Gloss (%)34.5 28.0 58.0 24.3 47.8 Clarity (%) 70.0 61.8 90.3 79.0 84.3 MD Tear(g) 159 129 188 170 146 CD Tear (g) 1,088 1,024 981 933 1,022 NormalizedMD Tear (g/mil) 80 65 98 89 75 Normalized CD Tear (g/mil) 550 514 501478 525 Dart Drop Impact (g) 181 157 169 181 190 Puncture (ft-lbf/in³)112 113 128 128 122 2% MD Secant Modulus (kpsi) 31.5 33.9 29.6 30.4 32.72% CD Secant Modulus (kpsi) 37.2 39.2 35.0 36.6 37.0 MD Shrink Tension(psi) 27.42 28.64 22.40 27.69 26.08 CD Shrink Tension (psi) 0.38 0.310.36 0.34 0.53 Thickness (mil) 2.03 2.06 1.97 1.96 2.00 Frost LineHeight (inches) 30 30 30 35 30 Melt Temperature (° F.) 442 442 440 443444 Rate Output (lb/hr) 247 251 249 250 250 Rate Output (lb/hr/in) 9.810.0 9.9 9.9 9.9 Screen Pressure (psi) 3,350 3,650 3,280 3,680 3,600

TABLE 16 Film properties of 20% LLDPE1/80% LDPE Films #38-42 made at 2mil at a standard (std.) rate of 250 lb/hr (8″ die). Film 38 39 40 41 42Component 1 (First Polymer) IE1 IE2 AGILITY LDPE LDPE 1001 662I 132I Wt% Component 1 80 80 80 80 80 Melt Index Component 2 0.58 0.37 0.64 0.380.25 Component 2 (Second Polymer) LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt% Component 2 20 20 20 20 20 Blown Film Rate Std. Std. Std. Std. Std.Haze (%) 19.4 25.3 9.8 38.8 13.5 Haze, Internal (%) 1.6 2.4 2.5 2.3 1.645 Degree Gloss (%) 32.4 23.9 55.7 16.5 43.0 Clarity (%) 69.7 60.7 88.944.2 83.3 MD Tear (g) 201 159 246 135 224 CD Tear (g) 340 336 369 317377 Normalized MD Tear (g/mil) 103 81 126 67 114 Normalized CD Tear(g/mil) 174 171 188 159 192 Dart Drop Impact (g) 169 145 163 154 172Puncture (ft-lbf/in³) 63 59 80 66 85 2% MD Secant Modulus (kpsi) 32.433.7 31.2 32.2 33.7 2% CD Secant Modulus (kpsi) 38.2 38.9 35.2 37.7 34.9MD Shrink Tension (psi) 35.80 42.34 24.91 41.80 32.65 CD Shrink Tension(psi) 0.58 0.81 0.47 0.37 0.52 Thickness (mil) 1.93 1.90 2.10 2.01 1.86Frost Line Height (inches) 35 35 35 35 35 Melt Temperature (° F.) 437439 435 441 442 Rate Output (lb/hr) 250 250 251 252 251 Rate Output(lb/hr/in) 9.9 9.9 10.0 10.0 10.0 Screen Pressure (psi) 2,830 3,0002,790 3,100 3,230

Blend Compositions

Blends of the same compositions used for the blown films were made forfurther characterization. The blend components were compounded using an“18 mm” twin screw extruder (micro-18). The twin screw extruder used wasa Leistritz machine controlled by Haake software. The extruder had fiveheated zones, a feed zone, and a “3 mm” strand die. The feed zone wascooled by flowing water, while the remaining zones 1-5 and the die wereelectrically heated and air cooled to 120, 135, 150, 190, 190, and 190°C., respectively. The pelletized polymer components were combined in aplastic bag, and tumble blended by hand. After preheating the extruder,the load cell and die pressure transducers were calibrated. The driveunit for the extruder was run at 200 rpm, which resulted by geartransfer to a screw speed of 250 rpm. The dry blend was then fed (6-8lbs/hr) to the extruder through a twin auger K-Tron feeder (model #K2VT20) using pellet augers. The hopper of the feeder was padded withnitrogen, and the feed cone to the extruder was covered with foil, tominimize air intrusion to minimize possible oxygen degradation of thepolymer. The resulting strand was water quenched, dried with an airknife, and pelletized with a Conair chopper.

Results are shown in Table 17 for compositions similar to those shown inTables 9-16, along with measured melt index, melt index ratio, density,and Mw, Mw/Mn, and Mz. The melt strength data are plotted in FIG. 4showing the differentiation and advantage of IE1 and IE2 as compared toall other LDPEs. IE2 shows similar behavior to autoclave LDPE 662I, butwithout the disadvantages of poor optics and gels that can result in afilm made autoclave resins.

TABLE 17 Properties of blend compositions with Component 2 being LLDPE 1(wt % component 1 + component 2 = 100 wt %). All MWD metrics in thistable obtained from GPC Method B. Blend Blend Blend Wt % Melt Melt BlendMelt Mw Mw/ Mz Component 1 Component Index I2 Index Density Strength(Conv.) Mn (Conv.) (First Polymer) 1 (dg/min) I10/I2 (g/cm³) (cN)(g/mole) (Conv.) (g/mole) NA NA 0.95 7.82 0.9195 3.0 116,405 4.48424,790 NA NA 0.92 7.92 0.9197 3.3 112,802 4.28 359,035 IE1 5 0.87 8.040.9200 7.7 115,378 4.58 375,719 IE2 5 0.85 8.20 0.9200 8.3 114,457 4.41355,947 AGILITY 1001 5 0.85 8.35 0.9202 8.1 112,877 4.68 367,415 LDPE662I 5 0.83 8.12 0.9199 8.6 119,170 4.56 403,479 LDPE 132I 5 0.83 8.300.9200 6.9 113,560 4.51 371,408 IE1 10 0.80 8.33 0.9200 11.3 116,7274.81 377,182 IE2 10 0.76 8.46 0.9202 12.9 117,557 4.63 380,858 AGILITY1001 10 0.82 8.52 0.9203 8.4 111,535 4.54 347,557 LDPE 662I 10 0.80 8.240.9204 12.1 122,082 4.69 417,770 LDPE 132I 10 0.74 8.63 0.9208 10.4113,259 4.58 373,270 IE1 20 0.66 9.26 0.9200 18.1 118,923 5.29 396,338IE2 20 0.64 9.39 0.9202 19.4 121,298 5.21 396,353 AGILITY 1001 20 0.729.15 0.9202 12.8 110,725 4.61 349,287 LDPE 662I 20 0.65 8.92 0.9200 18.8134,284 5.07 481,163 LDPE 132I 20 0.60 9.72 0.9206 15.0 113,934 4.85378,039 IE1 50 0.51 12.12 0.9198 30.1 129,948 6.64 424,669 IE2 50 0.4312.53 0.9197 32.2 136,584 7.09 457,937 AGILITY 1001 50 0.55 11.76 0.920820.6 108,229 5.32 338,591 LDPE 662I 50 0.42 11.57 0.9192 32.7 171,5536.89 629,965 LDPE 132I 50 0.37 12.27 0.9210 24.3 113,796 5.35 364,709IE1 80 0.45 15.98 0.9191 28.9 140,692 8.19 468,772 IE2 80 0.34 16.790.9193 29.4 151,185 9.06 513,576 AGILITY 1001 80 0.48 15.66 0.9204 23.0104,630 5.89 328,746 LDPE 662I 80 0.39 14.42 0.9192 29.1 205,602 9.00742,661 LDPE 132I 80 0.27 16.67 0.9209 25.0 138,463 6.87 503,623

1.-13. (canceled)
 14. A composition comprising the following: A) a firstethylene-based polymer, formed by a high pressure, free-radicalpolymerization process, and comprising the following properties: a) aMw(abs)/Mw(GPC)<2.2, and b) a MS versus I2 relationship: MS≥C×[(I2)^(D)], where C=13.5 cN/(dg/min)^(D), and D=−0.55, c) a melt index(2) from 0.1 to 0.9 g/10 min; and B) a second ethylene-based polymer;and wherein the second ethylene-based polymer has a melt index (2) from0.1 to 4.0 g/10 min; and wherein the first ethylene-based polymer ispolymerized in at least one tubular reactor.
 15. The composition ofclaim 14, wherein the first ethylene-based polymer has the followingproperty: a Mw(abs) versus I2 relationship: Mw(abs)<A×[(I2)^(B)], whereA=5.00×10² (kg/mole)/(dg/min)^(B), and B=−0.40 (Mw(abs) by GPC methodA).
 16. The composition of claim 14, wherein the first ethylene-basedpolymer has the following property: a Mw(abs) versus I2 relationship:Mw(abs)<A×[(I2)^(B)], where A=4.25×10² (kg/mole)/(dg/min)^(B), andB=−0.40 (Mw(abs) by GPC method A).
 17. The composition of claim 14,wherein the first ethylene-based polymer has a “weight fraction (w) ofmolecular weight greater than 10⁶ g/mole, based on the total weight ofpolymer, as determined by GPC(abs), that meets the followingrelationship: w<E×[(I2)^(F)], where E=0.110 (dg/min)^(−F), and F=−0.38(GPC Method A).
 18. The composition of claim 14, wherein the firstethylene-based polymer has a density from 0.910 to 0.940 g/cc (1 cc=1cm³).
 19. The composition of claim 14, wherein the first ethylene-basedpolymer has a density greater than, or equal to, 0.912 g/cc.
 20. Thecomposition of claim 14, wherein the first ethylene-based polymer has adensity greater than, or equal to, 0.915 g/cc.
 21. The composition ofclaim 14, wherein the first ethylene-based polymer has a density lessthan, or equal to, 0.935 g/cc.
 22. The composition of claim 14, whereinthe first ethylene-based polymer has a density less than, or equal to,0.930 g/cc.
 23. The composition of claim 14, wherein the firstethylene-based polymer has a density less than, or equal to, 0.925 g/cc.24. The composition of claim 14, wherein the first ethylene-basedpolymer has a density less than, or equal to, 0.920 g/cc.
 25. Thecomposition of claim 14, wherein the first ethylene-based polymer ispresent in an amount greater than 0.5 weight percent, based on the sumof the weight of first ethylene-based polymer and the secondethylene-based polymer.
 26. The composition of claim 14, wherein thesecond ethylene-based polymer present in an amount from 10 to 95 wt %,based on weight of the composition.
 27. The composition of claim 14,wherein the second ethylene-based polymer is an ethylene/α-olefininterpolymer.
 28. The composition of claim 27, wherein theethylene/α-olefin interpolymer is a heterogeneously branchedethylene/α-olefin interpolymer.
 29. The composition of claim 14, whereinthe composition has a density from 0.910 to 0.925 g/cc.
 30. Thecomposition of claim 14, wherein the composition has a melt index (I2)from 0.1 to 1.5 g/10 min.
 31. An article comprising at least onecomponent formed from the composition of claim
 14. 32. A film comprisingat least one layer formed from the composition of claim
 14. 33. The filmof claim 32, wherein the film comprises at least two layers.